The fact that there is a layer of white stuff floating on top of the wine means that the wine has been contaminated by stray bacteria and has developed mold. The main reason why homebrewed wine gets moldy is because it has too much contact with the air during fermentation and storage, so it breeds bacteria and deteriorates. Such wines are not drinkable.

The grapes used to make wine need to be ripe, unbroken and free of mold. While grapes are not easy to keep at room temperature and are prone to mold, if the freshness is not high, it will make the wine easy to breed mold.

Grapes in the brewing process, should not be excessive contact with the air, that is easy to make the wine oxidation, it is best to use non-metallic vessels, such as glass bottles, altars, etc., do not use plastic bottles, stainless steel, aluminum utensils, etc. to contain.

Expanded:

The flavonoids in wine can effectively scavenge free radicals and play an antioxidant role for some of the skin is easy to pigmentation of a glass of wine every day to help the skin fine and reduce facial pigmentation, but also slow down the growth of wrinkles in the skin to enhance the degree of firmness of the skin.

Wine contains some grapes and resveratrol, these resveratrol can effectively remove the diseased cells in the human body, to prevent the normal cells in the human body cancer. Moreover, some anthocyanins in wine can promote the expansion of blood vessels in the human body and reduce the harmful substances in blood vessels to prevent cardiovascular diseases such as vascular sclerosis.

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